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  • Articles: DFG German National Licenses  (7)
  • Serotonin  (3)
  • Hypothalamus  (2)
  • Opsin immunoreactivity  (2)
  • 1
    ISSN: 1432-0533
    Keywords: Key words Pineal parenchymal tumors ; Neuronal ; differentiation ; Tryptophan hydroxylase ; Serotonin ; N-acetyltransferase ; Hydroxyindole-O-methyltransferase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Using both tumor specimen and cultured tumor cells, we have studied the differentiation of a pineocytoma by light and electron microscopy (EM) and immunohistochemical demonstration of glial, neuronal and neuroendocrine markers. Only interstitial cells were labeled with anti-glial fibrillary acidic protein and anti-S100 protein antibodies. Synaptophysin, neurofilaments and tau labeling was found in cells forming the pineocytomatous rosettes. Some cells also bound the anti-tryptophan hydroxylase antibody (TPOH), but no staining was seen after application of anti-chromogranin A or S-antigen antibodies. EM provided evidence for neurosensory differentiation demonstrating the presence of vesicle-crowned rodlets, cilia (9+0) and fibrous filaments. In culture, tumor cells proliferated slowly and showed positive immunolabeling for vimentin and TPOH. Expression of mRNA coding for TPOH, serotonin N-acetyltransferase, hydroxyindole-O-methyl-transferase and c-myc was found in the tumor using reverse transcriptase-polymerase chain reaction. These results demonstrate neuronal differentiation of this pineocytoma and suggest that the neoplastic pineal cells are capable of synthesizing serotonin and melatonin.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1432-0878
    Keywords: Retina ; Pineal organ ; Hypothalamus ; Opsin ; α-Transducin ; Interstitial retinol-binding protein (IRBP) ; Immunocytochemistry ; Japanese quail
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The retinal proteins opsin,α-transducin, S-antigen and interstitial retinol-binding protein (IRBP) are essential for the processes of vision. By use of immunocyto-chemistry we have employed antibodies directed against these “photoreceptor proteins” in an attempt to identify the photoreceptor systems (retina, pineal and deep brain) of the Japanese quail. Opsin immunostaining was identified within many outer (basal portion) and inner segments of retinal photoreceptor cells and limited numbers of photoreceptor perikarya. Opsin immunostaining was also demonstrated in limited numbers of pinealocytes with all parts of these cells being immunoreactive. These results differ from previous observations. In contrast to the results obtained with the antibody against opsin, S-antigen andα-transducin immunostaining was seen throughout the entire outer segments and many photoreceptor perikarya of the retina. In the pineal organ immunostaining was seen in numerous pinealocytes in all follicles. These results conform to previous findings in birds. In addition, IRBP has been demonstrated for the first time in the avian retina and pineal organ. These findings underline the structural and functional similarities between the retina and pineal organ and provide additional support for a photoreceptive role of the avian pineal. No specific staining was detected in any other region of the brain in the Japanese quail; the hypothalamic photoreceptors of birds remain unidentified.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-0878
    Keywords: Pineal organ ; Parapineal organ ; Retina ; Photoreceptors ; Photoneuroendocrine system ; Rodopsin ; S-Antigen ; Serotonin ; Lampetra japonica (Cyclostomata)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pineal complex of the river lamprey, Lampetra japonica, was examined by means of immunocytochemistry with antisera against serotonin, the precursor of melatonin, and two photoreceptor proteins, rod-opsin (the apoprotein of the photopigment rhodopsin) and S-antigen. Serotonin-immunoreactive cells were observed in both the pineal and the parapineal organ. The proximal portion of the pineal organ (atrium) comprised numerous serotonin-immunoreactive cells displaying spherical somata. In the distal end-vesicle of the pineal organ, the serotonin-immunoreactive elements resembled photoreceptors in their size and shape. These cells projecting into the pineal lumen and toward the basal lamina were especially conspicuous in the ventral portion of the end-vesicle. In addition, single serotonin-immunoreactive nerve cells were found in this location. Retinal photoreceptors were never seen to contain immunoreactive serotonin; amacrine cells were the only retinal elements exhibiting serotonin immunoreaction. Strong S-antigen immunoreactivity was found in numerous photoreceptors located in the pineal end-vesicle. In contrast, the S-antigen immunoreactivity was weak in the spherical cells of the atrium. Thus, the pattern of S-antigen immunoreactivity was roughly opposite to that of serotonin. Similar findings were obtained in the parapineal organ. The rod-opsin immunoreaction was restricted to the outer segments of photoreceptors in the pineal end-vesicle and parapineal organ. No rodopsin immunoreactive outer segments occurred in the proximal portion of the atrium. Double immunostaining was employed to investigate whether immunoreactive opsin and serotonin are colocalized in one and the same cell. This approach revealed that (i) most of the rodopsin-immunoreactive outer segments in the end-vesicle belonged to serotonin-immunonegative photoreceptors; (ii) nearly all serotonin-immunoreactive cells in the end-vesicle bore short rod-opsin-immunoreactive outer segments protruding into the pineal lumen; and (iii) the spherical serotonin-immunoreactive cells in the pineal stalk lacked rod-opsin immunoreaction and an outer segment. These results support the concept that multiple cell lines of the photoreceptor type exist in the pineal complex at an early evolutionary stage.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-0878
    Keywords: Key words Dopamine-ß-hydroxylase ; Pineal organ ; S-antigen ; Serotonin ; Mouse (C57BL ; C3H)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Considerable progress is currently being made in elucidating the molecular basis of the circadian (photoneuroendocrine) system by use of transgenic mice generated from the inbred strains C57BL and C3H. As in all other vertebrate species, the pineal organ is an important component of the photoneuroendocrine system in these mouse strains, but very little is known about its morphological and immunocytochemical features. We therefore investigated the pineal organ and the adjacent epithalamic region of adult, 10-, and 5-day-old C57BL and C3H mice for S-antigen, serotonin, and dopamine-ß-hydroxylase (DBH) immunoreactions. In adult animals, the pineal organ was more than 2 times bigger in C3H than in C57BL mice. In younger animals, this difference was already evident, but less pronounced. The S-antigen immunoreactivity was more intense in adult C3H than in C57BL mice. This difference developed with increasing age; it was not yet detectable in 5-day-old animals. The intensity of the serotonin immunoreaction was similar in both strains at all stages investigated. However, the serotonin immunoreaction was more pronounced in adult than in young animals. The relative DBH-immunoreactive area (used as a marker for the sympathetic innervation of the pineal organ) was much bigger in C3H than in C57BL mice; within each strain it remained relatively constant during postnatal development. Adult individuals of both strains contained S-antigen- and serotonin-immunoreactive cells in the habenular complex. Their number increased with age, but they were always more numerous in C3H. In conclusion, the study has shown considerable differences in pineal morphology between C3H and C57BL, which may be related to the well-known differen- ces in melatonin formation between these two strains.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-0878
    Keywords: Pineal organ ; Parapineal organ ; Opsin immunoreactivity ; Cyclostome (Lampetra fluviatilis) ; Teleosts (Anguilla anguilla, Salmo gairdneri)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pineal complex of Lampetra fluviatilis, Anguilla anguilla and Salmo gairdneri was studied by means of the indirect immunohistochemical antiopsin reaction. Opsin-immunoreactive material was demonstrated in the outer segments of the photoreceptor cells in the pineal organ of all three species investigated. In the lamprey, the opsin-positive outer segments were located in the lumen of the pineal vesicle and atrium. In the two teleost species, the immunoreactive outer segments were observed in abundance in the pineal end-vesicle and stalk. These structures were found to accumulate in the prominent initial portion of the pineal stalk of the eel. In the rainbow trout, immunoreactive outer segments occurred in the wide orifice of the pineal recess at the roof of the third ventricle. In addition, outer segments of photoreceptor cells of the parapineal organ (“parapinealocytes”) displayed opsin immunoreactivity. In the lamprey, opsin immunoreactivity was restricted to the central portion of the ventral parapineal retina, while the parapinealocytes in the lateral portions did not bind the antibody. In the two teleosts, immunoreactive outer segments displayed a scattered pattern. These immunocytochemical results provide direct evidence that the photosensitivity of the pineal demonstrated electrophysiologically in lampreys and teleosts (cf. Dodt 1973) is based on an opsin-containing photopigment. The presence of opsin in cells of the parapineal organ strengthens the view that also this organ may be capable of direct light perception. In the lamprey, the exclusive opsin immunoreactivity of a circumscribed group of parapineal cells suggests the existence of two types of parapinealocytes. The significance of opsin-containing photoreceptor outer segments occurring in the most proximal portion of the teleost pineal stalk is discussed, especially with regard to the interpretation of results obtained from pinealectomy experiments.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1432-0878
    Keywords: CSF-contacting neurons ; Somatostatin immunocytochemistry ; Hypothalamus ; Entopeduncular nucleus ; Pretectal area ; Tegmentum ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A system of somatostatin-immunoreactive neurons was demonstrated in the brains of the eel, Anguilla anguilla, the European minnow, Phoxinus phoxinus, and the rainbow trout, Salmo gairdneri, by means of the light-microscopic indirect immunoperoxidase technique. In the anterior periventricular nucleus, somatostatin-immunoreactive cerebrospinal fluid (CSF)-contacting neurons display intensely stained intraventricular dendritic protrusions, perikarya, and axonal processes. The latter taper into a somatostatin-immunoreactive fiber plexus extending to the infundibulum, the proximal neurohypophysis, and the lateral and mammillary recesses. In addition, somatostatin-immunoreactive neurons were demonstrated in the magnocellular preoptic, entopeduncular and dorsolateral thalamic nuclei, further in the pretectal area and the ventrolateral tegmentum. Somatostatin-immunoreactive fiber bundles project via the stria medullaris toward the habenular nucleus; they also course in the dorsomedial-ventrolateral direction at the level of the pretectal-tegmental area, and within the ventral and dorsal tegmentum. The presence of somatostatin in a variety of different neurons of the teleost brain is discussed in connection with their tentative inhibitory function. The CSF-contacting neurons of the anterior periventricular nucleus are supposed to function as sensors that pass information from the CSF to the somatostatin system of the hypothalamus and/or other components of the neuroendocrine apparatus.
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  • 7
    ISSN: 1432-0878
    Keywords: Pineal photoreceptors ; Opsin immunoreactivity ; Pineal neurons ; Acetylcholinesterase reaction ; Parapineal organ ; Teleosts (Phoxinus phoxinus L.)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pineal complex of the teleost, Phoxinus phoxinus L., was studied light-microscopically by the use of the indirect immunocytochemical antiopsin reaction and the histochemical acetylcholinersterase (AChE) method. Opsin-immunoreactive outer segments of photoreceptor cells were demonstrated in large numbers in all divisions of the pineal end-vesicle and in the pineal stalk. Moreover, they were found in the roof of the third ventricle, adjacent to the orifice of the pineal recess as well as scattered in the parapineal organ. These immunocytochemical observations provide direct evidence of the presence of an opsin associated with a photopigment in the photosensory cells of the pineal and parapineal organs of Phoxinus. By means of the AChE reaction (Karnovsky and Roots 1964) inner segments of pineal photoreceptors, intrinsic nerve cells, several intrapineal bundles of nerve fibers, and a prominent pineal tract were specifically marked. The pineal neurons can be divided into two types: one is located near the pineal lumen, the other near the basal lamina. The latter perikarya bear stained processes directed toward the photoreceptor layer. A rostral aggregation of two types of AChE-positive nerve cells occurs in the ventral wall of the pineal end-vesicle. The main portion of the AChE-positive pineal tract, which lies within the dorsal wall of the pineal stalk, can be followed to the posterior commissure where some of the nerve fibers course laterally. A few AChE-positive pineal nerve fibers run toward the lateral habenular nucleus via the habenular commissure. In the region of the subcommissural organ single AChE-positive neurons accompany the pineal tract. The nerve cells of the parapineal organ exhibit a moderate AChE activity. These findings extend the structural basis for the remarkable light-dependent activity of the pineal organ of Phoxinus phoxinus.
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